A post quantum secure construction of an authentication protocol for satellite communication

Satellite's communication system is used to communicate under significant distance and circumstances where the other communication systems are not comfortable. Since all the data are exchanged over a public channel, so the security of the data is an essential component for the communicating parties. Both key exchange and authentication are two cryptographic tools to establish a secure communication between two parties. Currently, various kinds of authentication protocols are available to establish a secure network, but all of them depend on number–theoretical (discrete logarithm problem/factorization assumption) hard assumptions. Due to Shor's and Grover's computing algorithm number theoretic assumptions are breakable by quantum computers. Although Kumar and Garg have proposed a quantum attack-resistant protocol for satellite communication, it cannot resist stolen smart card attack. We have analyzed that how Kumar and Garg is vulnerable to the stolen smart card attack using differential power analysis attack described in He et al and Chen and Chen. We have also analyzed the modified version of signal leakage attack and sometimes called improved signal leakage attack on Kumar and Garg's protocol. We have tried to construct a secure and efficient authentication protocol for satellites communication that is secure against quantum computing. This is more efficient as it requires only three messages of exchange. This paper includes security proof and performance of the proposed authentication and key agreement protocol.     

Influence of 2,3-Dihydroxyflavanone on Corrosion Inhibition of Mild Steel in Acidic Medium

The inhibition effect of 2,3-dihydroxyflavone on the corrosion of mild steel in 100-600 ppm aqueous hydrochloric acid solution has been investigated by weight loss and electrochemical impedance spectroscopy. The corrosion inhibition efficiency increases with increasing concentration and time. The effect of temperature on the corrosion behavior of mild steel in 1 M HCl with addition of inhibitor was studied at the temperature range of 300-330 K. UV-Vis, FTIR, and surface analysis (SEM) was also carried out to establish the corrosion inhibitive property of this inhibitor in HCl solution. The adsorption of this inhibitor on the mild steel surface obeys the Langmuir adsorption isotherm. Electrochemical studies reveal that the inhibitor is a cathodic type.     

Gecko‐Inspired Dry Adhesive for Robotic Applications

Most geckos can rapidly attach and detach from almost any kind of surface. This ability is attributed to the hierarchical structure of their feet (involving toe pads, setal arrays, and spatulae), and how they are moved (articulated) to generate strong adhesion and friction forces on gripping that rapidly relax on releasing. Inspired by the gecko's bioadhesive system, various structured surfaces have been fabricated suitable for robotic applications. In this study, x–y–z asymmetric, micrometer‐sized rectangular flaps composed of polydimethylsiloxane (PDMS) were fabricated using massively parallel micro‐electromechanical systems (MEMS) techniques with the intention of creating directionally responsive, high‐to‐low frictional‐adhesion toe pads exhibiting properties similar to those found in geckos. Using a surface forces apparatus (SFA), the friction and adhesion forces of both vertical (symmetric) and angled/tilted (x–y–z asymmetric) microflaps under various loading, unloading and shearing conditIons were investigated. It was found that the anisotropic structure of tilted microflaps gives very different adhesion and tribological forces when articulated along different x–y–z directions: high friction and adhesion forces when articulated in the y–z plane along the tilt (+y) direction, which is also the direction of motion, and weak friction and adhesion forces when articulated against the tilt (–y) direction. These results demonstrate that asymmetric angled structures, as occur in geckos, are required to enable the gecko to optimize the requirements of high friction and adhesion on gripping, and low frictional‐adhesion on releasing. These properties are intimately coupled to a (also optimum) articulation mechanism. We discuss how both of these features can be simultaneously optimized in the design of robotic systems that can mimic the gecko adhesive system.     

CoopMAC: A Cooperative MAC for Wireless LANs

Due to the broadcast nature of wireless signals, a wireless transmission intended for a particular destination station can be overheard by other neighboring stations. A focus of recent research activities in cooperative communications is to achieve spatial diversity gains by requiring these neighboring stations to retransmit the overheard information to the final destination. In this paper we demonstrate that such cooperation among stations in a wireless LAN (WLAN) can achieve both higher throughput and lower interference. We present the design for a medium access control protocol called CoopMAC, in which high data rate stations assist low data rate stations in their transmission by forwarding their traffic. In our proposed protocol, using the overheard transmissions, each low data rate node maintains a table, called a CoopTable, of potential helper nodes that can assist in its transmissions. During transmission, each low data rate node selects either direct transmission or transmission through a helper node in order to minimize the total transmission time. Using analysis, simulation and testbed experimentation, we quantify the increase in the total network throughput, and the reduction in delay, if such cooperative transmissions are utilized. The CoopMAC protocol is simple and backward compatible with the legacy 802.11 system. In this paper, we also demonstrate a reduction in the signal-to-interference ratio in a dense deployment of 802.11 access points, which in some cases is a more important consequence of cooperation     

Stick–slip friction of gecko-mimetic flaps on smooth and rough surfaces

The discovery and understanding of gecko ‘frictional-adhesion’ adhering and climbing mechanism has allowed researchers to mimic and create gecko-inspired adhesives. A few experimental and theoretical approaches have been taken to understand the effect of surface roughness on synthetic adhesive performance, and the implications of stick–slip friction during shearing. This work extends previous studies by using a modified surface forces apparatus to quantitatively measure and model frictional forces between arrays of polydimethylsiloxane gecko footpad-mimetic tilted microflaps against smooth and rough glass surfaces. Constant attachments and detachments occur between the surfaces during shearing, as described by an avalanche model. These detachments ultimately result in failure of the adhesion interface and have been characterized in this study. Stick–slip friction disappears with increasing velocity when the flaps are sheared against a smooth silica surface; however, stick–slip was always present at all velocities and loads tested when shearing the flaps against rough glass surfaces. These results demonstrate the significance of pre-load, shearing velocity, shearing distances, commensurability and shearing direction of gecko-mimetic adhesives and provide us a simple model for analysing and/or designing such systems.     

Squirrel search algorithm for economic dispatch with valve-point effects and multiple fuels

ABSTRACT

This paper bestows a new swarm intelligence approach, Squirrel Search Algorithm (SSA) to solve Economic Load Dispatch (ELD) of the thermal unit by addressing the valve point loading effects and multiple fuel options. SSA inspires the foraging behavior of squirrels which is based on dynamic jumping and gliding strategies. The main intention of the ELD problem is to minimize the total generation cost of units while assuring various system constraints. Renovate strategy and selection rules are used in the SSA algorithm to handle the constraints appropriately. The practicability of the proposed algorithm is tested on six different power test systems having different sizes and intricacies. Simulation results ascertain that the proposed SSA approach outperforms the other existing heuristic optimization techniques in terms of solution quality, robustness, and computational efficiency. Consequently, the proposed SSA can be an efficient approach for solving the ELD problems with valve point loading impacts and multi-fuel options.     

Usage-based dynamic pricing of Web services for optimizing resource allocation

Web services technology is becoming an important technological trend in Web application development and integration. Based on open standards, such as SOAP, WSDL, and UDDI, Web services allow Web-based applications to communicate with each other through standardized XML messaging and to form loosely coupled distributed systems. Although the open feature of Web services benefits service providers in servicing consumers, the unlimited computing resources access of Web services to network bandwidth, storage throughput, and CPU time may lead to overexploitation of the resources when applications based on the Web services technology are widely accepted. Therefore, it is critical to optimize the operation of Web services, subject to the QoS requirements of service requests, to assure the total benefits of the service providers and the service consumers. This paper proposes a usage-based dynamic pricing approach to optimizing resource allocation of Web services in the principle of economics, and reports on a pilot implementation demonstrating the technical feasibility of the proposed approach.

Hidden location prediction using check-in patterns in location-based social networks

Online product reviews nowadays are increasingly prevalent in E-commerce websites. People often refer to product reviews to evaluate the quality of a product before purchasing. However, there have been a large number of review spammers who often work collaboratively to promote or demote target products, which severely harm the review system. Much previous work exploits machine learning approaches to detect suspicious reviews/reviewers. In this paper, we introduce a top-down computing framework, namely GGSpam, to detect review spammer groups by exploiting the topological structure of the underlying reviewer graph which reveals the co-review collusiveness. A novel instantiation of GGSpam, namely GSBC, is designed by modeling spammer groups as bi-connected graphs. Given a reviewer graph, GSBC identifies all the bi-connected components whose spamicity scores exceed the given spam threshold. For large unsuspicious bi-connected graphs, the minimum cut algorithm is used to split the graph, and the smaller graphs are further processed recursively. A variety of group spam indicators are designed to measure the spamicity of a spammer group. Experimental study shows that the proposed approach is both effective and efficient and outperforms several state-of-the-art baselines, including graph based and non-graph based, by a large margin.     

RETRACTED ARTICLE: An Energy Efficient Framework for Densely Distributed WSNs IoT Devices Based on Tree Based Robust Cluster Head

With the development of the internet of things, which is widely applied not only to everyday objects but also to industrial areas, the production of big data is accelerating. To provide intelligent services without human intervention in the internet of things environment, intelligent communication between objects becomes the key, and since the failure of the mechanical equipment attached to the sensor causes malfunction of the object and product failure, big data analysis to predict equipment failure is becoming more important. The purpose of this study is to propose a model for predicting mechanical equipment failure from various sense data collected in the manufacturing process. This study constructed a RHadoop-based big data platform to distribute a large amount of datasets for research, and performed logistic regression modeling to predict the main variables causing the failure from various collected variables. As a result of the study, the main variables in the manufacturing process that cause equipment failure were derived from the collected sense data, and the fitness and performance evaluation for the prediction model were made using the ROC curve. As a result of the performance evaluation of the prediction model, the ROC curve showed a fairly high prediction accuracy with AUC close to 1. The results of this study are expected to be applicable to the prediction of malfunctions, product failure, or abnormal communication between objects due to miscellaneous product faults in our daily lives in the internet of things environment.     

Influence of grain boundary sliding on diffusion in yttria doped zirconia

Grain boundary sliding during high temperature deformation can lead to stress concentrations and an enhancement of diffusion in mobile boundaries. Experiments were conducted on a fine grained 3 mol% yttria stabilized tetragonal zirconia, under conditions associated with superplastic flow involving grain boundary sliding. Tracer diffusion studies under creep conditions and without load indicate that there is no enhancement in either the lattice or grain boundary diffusivities. The experimental creep data are consistent with an interface controlled diffusion creep mechanism.